man-tram 

A male (usually rotund) who’s always on the bottom during sexual intercourse; thus always being ridden like a tram, or trolley car.

Since my boyfriend put on weight he's become a total man-tram. I just feel like I'm always doing all the work in bed.

man-tram by MAX L0AD July 29, 2012

man trampoline 

when having sex a girl is bouncing on a man

going up and down on a dick is a man trampoline

man trampoline by im your dad bobby December 5, 2019

Little Man on the Trampoline

The act of grabbing the sides of your scrotum and pulling it taught whilst you bounce your penis up and down on it.

My girl likes it when I show her the "little man on the trampoline"

Little Man on the Trampoline by Steve-o and Tim December 15, 2008

Trampo wampo man 

He always tries to win the trampoline competition but does not make it past other people’s shoes

Trampo wampo man can’t reach my shoe

Trampo wampo man by G_Normz22 February 1, 2021